The Trail of Discovery Click to enlarge A series of seafloor photos taken by ANGUS shows the sudden appearance of a dense accumulation of live white clams. Within hours, the clams led scientists to find hydrothermal vents for the first time. (Courtesy of WHOI Archives) 1977 - Astounding Undersea Discoveries Thirteen fateful photos After 12 hours, ANGUS ran out of film. It had shot 3,000 color photos over 16 kilometers (7.25 miles) of seafloor. When the film was developed, the scientists studied the photos, starting from the first one. They looked at hundreds of photos, frame by frame, until they reached the photos that corresponded with the time when the temperature spike, or “anomaly,” occurred. Notes on a Major Oceanographic Find By Robert Ballard In a 1977 article in Oceanus magazine called “Notes on a Major Oceanographic Find,” Bob Ballard recalled the surprising findings: “The photograph taken just seconds before the temperature anomaly showed only barren, fresh-looking lava terrain. But for thirteen frames (the length of the anomaly) the lava flow was covered with hundreds of white clams and brown mussel shells. This dense accumulation, never seen before in the deep sea, quickly appeared through a cloud of misty blue water and then disappeared from view. For the remaining 1,500 pictures, the bottom was once again barren of life.” Unlike the piles of empty clamshells found by the Pleiades expedition, these clams were clearly thriving.  Page 3 Page 5